CA2403440C - Process for producing oxirane compound - Google Patents

Process for producing oxirane compound Download PDF

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Publication number
CA2403440C
CA2403440C CA002403440A CA2403440A CA2403440C CA 2403440 C CA2403440 C CA 2403440C CA 002403440 A CA002403440 A CA 002403440A CA 2403440 A CA2403440 A CA 2403440A CA 2403440 C CA2403440 C CA 2403440C
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Prior art keywords
catalyst
catalyst bed
olefin
ethylbenzene hydroperoxide
supplied
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Expired - Fee Related
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CA002403440A
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French (fr)
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CA2403440A1 (en
Inventor
Noriaki Oku
Tateo Seo
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Sumitomo Chemical Co Ltd
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Sumitomo Chemical Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D301/00Preparation of oxiranes
    • C07D301/02Synthesis of the oxirane ring
    • C07D301/03Synthesis of the oxirane ring by oxidation of unsaturated compounds, or of mixtures of unsaturated and saturated compounds
    • C07D301/19Synthesis of the oxirane ring by oxidation of unsaturated compounds, or of mixtures of unsaturated and saturated compounds with organic hydroperoxides
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00Technologies relating to chemical industry
    • Y02P20/50Improvements relating to the production of bulk chemicals
    • Y02P20/52Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Epoxy Compounds (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

A process for producing an oxirane compound from ethylbenzene hydroperoxide and an olefin in the presence of an immobilized catalyst bed, wherein the process satisfies the following conditions (1) to (4):

(1) the catalyst bed is divided into n catalyst beds and the catalyst beds are used in series, wherein n is an integer of 2 or more, (2) fresh ethylbenzene hydroperoxide is divided into portions, which are supplied to respective inlets of the catalyst beds, (3) fresh olefin is supplied to the inlet of the first catalyst bed, and (4) the reaction mixture discharged from each outlet of respective catalyst beds excluding the final catalyst bed is supplied to the inlet of the subsequent catalyst bed.

Description

SPECIFICATION
PROCESS FOR PRODUCING OXIRANS COMPOUND
TECHNICAL FIELD

The present invention relates to a process for producing an oxirane compound. More particularly, the invention relates to a process for producing an oxirane compound from ethylbenzene hydroperoxide and an olef in in the presence of an immobilized catalyst bed, wherein said process for producing an oxirane compound has excellent characteristics that it can prevent a runaway of a reaction accompanied with generation of heat and can be stably carried out under a high yield.

BACKGROUND ART

Techniques for producing an oxirane compound from ethylbenzene hydroperoxide and an olefin in the presence of an immobilized catalyst bed have been publicly known. Since the reaction producing an oxirane compound from ethylbenzene hydroperoxide and an olefin is an exothermic reaction, there have been problems that the reaction accompanies a sudden generation of heat in the immobilized catalyst bed, thereby making difficult a stable run, and sometimes not only the catalyst is deteriorated but also the yield is lowered.

DISCLOSURE OF INVENTION

An object of the present invention is to provide a process for producing an oxirane compound from ethylbenzene hydroperoxide and an olef in in the presence of an immobilized catalyst bed, wherein said process for produci.ng an oxirane compound has excellent characteristics that it can prevent a runaway of a reaction accompanied with generation of heat and can be stably carried out with a high yield.

Namely, the present invention relates to a process for producing an oxirane compound from ethylbenzene hydroperoxide and an olefin in the presence of an immobilized catalyst bed, wherein the process satisfies the following conditions (1) to (4):

(1) the catalyst bed is divided into n catalyst beds and the catalyst beds are used in series, wherein n is an integer of 2 or more, (2) fresh ethylbenzene hydroperoxide is divided into n portions, which are supplied to respective inlets of the catalyst beds, (3) fresh olefin is supplied to the inlet of the f irst catalyst bed, and (4) the reaction mixture discharged from each outlet of respective catalyst beds excluding the final catalyst bed is supplied to the inlet of the subsequent catalyst bed.

BRIEF DESCRIPTION OF THE DRAWING

Figures 1 to 3 show examples of embodiment s for practicing the invention and Figure 4 shows an embodiment according to Comparative Example 1.

1. catalyst bed, 2. fresh ethylbenzene hydroperoxide, 3. fresh olefin, 4. Cooling equipment BEST MODE FOR CARRYING OUT THE INVENTION

Examples of the olefin used in the present invention can include propylene, hexene, octene and the like. When propylene is used as the olef in, propylene oxide is obtained as the oxirane compound.

The catalyst used in the present invention can include a titanium-containing silicon oxide catalyst and the like.
Among them, a titanium-containing silicon oxide catalyst is preferred from the viewpoint that it allows attainment of a high yield and a high selectivity.

The process for production according to the present invention satisfies the following conditions (1) to (4):
(1) the catalyst bed is divided into n catalyst beds and the catalyst beds are used in series, wherein n i.s an integer of 2 or more, (2) fresh ethylbenzene hydroperoxide is divided into n portions, which are supplied to respective inlets of the catalyst beds, (3) fresh olefin is supplied to the inlet of the first catalyst bed, and (4) the reaction mixture discharged from each outlet of respective catalyst beds excluding the final catalyst bed is supplied to the inlet of the subsequent catalyst bed.

The condition (1) is to divide the catalyst bed into n beds and use them in series. The expression "use in series" means a connection of catalyst beds in which a reaction mixture from an outlet of a certain divided catalyst bed is supplied to an inlet of the subsequent catalyst bed and finally a reaction mixture is obtained from an outlet of the n-th catalyst bed. Additionally, n is an integer of 2 or more and is usually 2 to 20. Methods for dividing the catalyst bed for distributing the heat of reaction include a method in which independently placed n reactors containing the catalyst are used (Fig. 1), a method in which catalyst beds are placed in partitions in one reactor (Fig. 2) and the like. The divided catalyst beds may be the same or different in the kind or amount of the catalyst charged.

The condition( 2) is to divide and supply fresh ethylbenzene hydroperoxide to respective inlets of the catalyst beds (see Fig. 1 and Fig. 2). The term "fresh ethylbenzene hydroperoxide"
means ethylbenzene hydroperoxide supplied from outside of the system constituted according to the present invention.

The condition (3) is to supply an fresh olef in to an inlet of the first catalyst bed (see Fig. 1 and Fig. 2). The term fresh olefin means an olefin supplied from outside of the system constituted according to the invention. It is preferred that the total amount of the fresh olefin is supplied to an inlet of the first catalyst bed, but a part of the fresh olefin may be divided and supplied to other place ( s) than the inlet of the first catalyst bed insofar as the effect of the present invention is not deteriorated.

The condition(4) is to supply the reaction mixture discharged from each outlet of respective catalyst beds excluding the final catalyst bed to the inlet of the subsequent catalyst bed (see Fig. 1 and Fig. 2). In other words, the reaction mixture discharged from an outlet of a catalyst bed serially passes through catalyst bed(s) in order. A part of the reaction mixture discharged from an outlet of a catalyst bed may be recycled to the inlet of the same catalyst bed insofar as the effect of the 5 invention is not deteriorated. This is effective for preventing a rise in temperature caused by the heat of reaction in the catalyst bed.

By satisfying the above- described conditions, the present invention realizes the effect that a runaway of reaction accompanied by generation of heat can be prevented and an oxirane compound can be stably produced with high yield. In other words , it allows suppression of lowering in the catalyst activity by thermal deterioration, shortening of the catalyst life, lowering in the yieid, runaway of the reaction and the like due to generation of heat accompanied by the reaction of ethylbenzene hydroperoxide and an olef in. Since the epoxidation reaction between ethylbenzene hydroperoxide and an olef in generates very abundant heat and is highly temperature-dependent, the reaction has a high danger of reaction runaway. Generally, the amount of reaction has been adjusted by controlling the temperature at the inlet of the catalyst bed or by compulsorily removing heat from the outside. However, it has become difficult to set the reaction temperature with accuracy according to the activity of a specific catalyst owing to a change in the catalyst activity with time or difference in time between the outlet and the inlet of the reactor, and therefore, not only problems arises that the activity of the catalyst is lowered and the yield decreases due to sudden increase in the amount of reaction and outflow of unreacted organic peroxide, but also there is a problem in stable operation. According to the present invention, the rise in temperature by the heat of the reaction can be controlled by partitioning the catalyst bed and adjusting feeding amount to respective catalyst beds; therefore, it becomes possible to prevent lowering in the catalyst activity and decrease in the yield accompanied by sudden rise in temperature in the catalyst bed, and additionally, the runaway of the reaction by a rise in the reaction temperature. In the present invention, a heat -removing apparatus such as a heat exchanger may be equipped between catalyst beds. This allows control of the temperature at the inlet of each catalyst bed, and together with the control of feeding amount of ethylbenzene hydroperoxide, provides double-safety and -steady operation.

Furthermore, a catalyst bed without a feed of fresh ethylbenzene hydroperoxide may be placed subsequent to the last divided catalyst bed. This is effective for treating unreacted ethylbenzene hydroperoxide in the reaction mixture discharged from the outlet of the last catalyst bed.

The epoxidation temperature is generally 0 to 200 C and preferably 25 to 200 C. The pressure may be any pressure sufficient to keep liquid state of the reaction mixture.
Generally, the pressure is advantageously 100 to 10,000 ]kPa.
The amount of an olef in fed is 1 to 100 times, preferably 3 to 50 times, more preferably 5 to 20 times, based on the total molar number of ethylbenzene hydroperoxide fed to catalyst beds.
Usually, unreacted olefin is recycled after separation and purification and used as the raw material for the epaxidation reaction.

In a specific example of the reaction, a case wherein propylene oxide is produced from propylene and ethylbenzene hydroperoxide is described below. The reaction can be carried out in a liquid phase using a solvent. The solvent is a liquid at the temperature and the pressure of the reaction and must be substantially inert to the reactants and the product. The solvent may be composed of a substance existing in a solution of ethylbenzene hydroperoxide actually used. Usually, the concentration of ethylbenzene hydroperoxide is 5 to 50* byweight and preferably 10 to 40$ by weight. When, for example, it is a mixture with ethylbenzene as the raw material, said material may be used for a solvent without adding a solvent in particular.
Other useful solvents include monocyclic aromatic compounds (e. g.

benzene, toluene, chlorobenzene, o-dichlorobenzene), alkanes (e.g. octane, decane, dodecane) and the like. When a titanium-containing silicon compound catalyst is used as the catalyst, propylene oxide is obtained at a reaction pressure of 1 to 10 MPa and a reaction temperature of 50 to 150 C with a feed of 1 to 20 times by mole of propylene based on the molar amount of fresh ethylbenzene hydroperoxide fed. Unreacted propylene is recycled to the epoxidation step after separation and purification, and reused.

EXAMPLES
Example 1 Referring to Fig. 3, each 2 g and total 8 g of Ti-containing silicon oxide catalyst is charged in a fixed-bed flow reactor composed of four independent catalyst beds, and 10 g/hour of a solution containing 30-t byweight of ethylbenzene hydroperoxide is fed in 2.5 g/hour portions to the four catalyst beds. On the other hand, 15 g/hour of propylene is fed to the first catalyst bed. The reaction mixture discharged from the outlet of the first catalyst bed is cooled by a cooling equipment, and the total amount is fed to the second catalyst bed together with the divided 2.5 g/hour amount of the fresh ethylbenzene hydroperoxide raw material. The reaction mixture discharged from the outlet of the second catalyst bed is cooled, and the total amount is fed to the third catalyst bed together with the divided fresh ethylbenzene hydroperoxide raw material. The reaction mixture discharged from the outlet of the third catalyst bed is cooled, and the total amount is fed to the fourth catalyst bed together with the divided fresh ethylbenzene hydroperoxide raw material. The pressure at the respective catalyst beds is adjusted to 7.0 MPa, and the temperature at the inlet of the respective catalyst beds is adjusted such that the conversion of the fed ethylbenzene hydroperoxide becomes 99%. The results of reaction in this case are shown in Table 1.

Comparative Example 1 Referring to Fig. 4, 8 g of the same catalyst as that in Example 1 is charged in a single catalyst bed, and 10 g/hour of the same solution as that in Example 1 containing 30% by weight of ethylbenzene hydroperoxide and 15 g/hour of the same propylene as that in Example 1 are fed thereto. The pressure at the catalyst bed is adjusted to 7.0 MPa, and the temperature at the inlet of the catalyst bed is adjusted such that the conversion of the fed ethylbenzene hydroperoxide becomes 99%. The results of reaction in this case are shown in Table 2, indicating that the yield of propylene decreases and produced amount of acetophenone and phenol formed by thermal decomposition of ethylbenzene hydroperoxide increases.

[Table 1]

First Second Third Fourth catalyst catalyst catalyst catalyst Total bed bed bed bed Conversion of EHP

(t) Yield of PO/C3' ($) ACP/EHP

(~) PNL/EHP
0.5 0.5 0.5 0.5 0.5 (~) [Table 2]

Total Conversion of EHP

($) Yield of PO/C3' ($) ACP / EHP

($) PNL/EHP

($) [Description for Tables]

EHP: Ethylbenzene hydroperoxide PO: Propylene oxide C3': Propylene ACP: Acetophenone 5 PNL: Phenol Conversion of EHP: [Reacted EHP/Supplied EHP] x 100 ($) Yield of PO/C3': [Produced PO (mol)/Reacted C3' (mol)] x 100 ($) ACP/EHP: [Produced ACP (mol)/Reacted EHP (mol)] x 100 ($) 10 PNL/EHP : [Produced PNL (mol )=/Reacted EHP (mol ) ] x 100 ( $ ) INDUSTRIAL APPLICABILITY

As described above, according to the present invention, a process for producing an oxirane compound from ethylbenzene hydroperoxide and an olefin in the presence of immobilized catalyst beds, said process for producing an oxirane compound, having excellent characteristics that it can prevent a runaway of reaction accompanied by generation of heat and can be stably carried out with high yield, can be provided.

Claims (9)

CLAIMS:
1. A process for producing an oxirane compound from ethylbenzene hydroperoxide and an olefin in the presence of an immobilized catalyst bed, wherein the process satisfies the following conditions (1) to (4):

(1) the catalyst bed is divided into n catalyst beds and the catalyst beds are used in series, wherein n is an integer of 2 or more, (2) fresh ethylbenzene hydroperoxide is divided into n portions, which are supplied to respective inlets of the catalyst beds, (3) fresh olefin is supplied to the inlet of the first catalyst bed, and (4) the reaction mixture discharged from each outlet of respective catalyst beds excluding the final catalyst bed is supplied to the inlet of the subsequent catalyst bed.
2. The process according to claim 1, wherein the catalyst is a titanium-containing silicon oxide catalyst.
3. The process according to claim 1 or 2, wherein the olefin is propylene, hexene or octene.
4. The process according to claim 1 or 2, wherein the olefin is propylene, thereby producing propylene oxide as the oxirane compound.
5. The process according to any one of claims 1 to 4, wherein n is an integer of from 2 to 20.
6. The process according to any one of claims 1 to 5, which employs independently placed n reactors each containing one of the catalyst bed.
7. The process according to any one of claims 1 to 5, which employs one reactor having therein n partitions each containing one of the catalyst bed.
8. The process according to any one of claims 1 to 7, wherein the reaction mixture discharged from each outlet of respective catalyst beds excluding the final catalyst bed is cooled before being supplied to the inlet of the subsequent catalyst bed.
9. The process according to any one of claims 1 to 8, which is conducted at a pressure of 1 to 10 MPa and a temperature of 50 to 150°C at each catalyst bed with a feed of 1 to 20 moles of propylene as the olefin per mole of ethylbenzene hydroperoxide.
CA002403440A 2000-03-24 2001-03-19 Process for producing oxirane compound Expired - Fee Related CA2403440C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2000-83964 2000-03-24
JP2000083964A JP2001270879A (en) 2000-03-24 2000-03-24 Method for producing oxirane compound
PCT/JP2001/002188 WO2001070712A1 (en) 2000-03-24 2001-03-19 Process for producing oxirane compound

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CA2403440A1 CA2403440A1 (en) 2002-09-19
CA2403440C true CA2403440C (en) 2009-08-18

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US (1) US6646140B2 (en)
EP (1) EP1266892B1 (en)
JP (1) JP2001270879A (en)
KR (1) KR100784119B1 (en)
CN (1) CN1196690C (en)
AT (1) ATE346054T1 (en)
AU (1) AU2001241206A1 (en)
BR (1) BR0109333A (en)
CA (1) CA2403440C (en)
DE (1) DE60124682D1 (en)
ES (1) ES2275660T3 (en)
WO (1) WO2001070712A1 (en)

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EP1453818B1 (en) * 2001-12-05 2005-11-09 Dow Global Technologies Inc. Process of preparing an olefin oxide from olefin and organic hydroperoxide
US6562987B1 (en) * 2002-02-28 2003-05-13 Arco Chemical Technology, L.P. Method for highly exothermic epoxidation reactions
US7294726B2 (en) 2002-04-03 2007-11-13 Shell Oil Company Process for preparing alkylene oxide
DE10234448A1 (en) * 2002-07-29 2004-02-12 Basf Ag Process for the production of propylene oxide using a post-reactor with multiple feed and / or discharge points
CN101885711B (en) * 2009-05-13 2012-09-05 中国石油化工股份有限公司 Production method of propylene oxide
CN101941954B (en) * 2009-07-06 2012-09-05 中国石油化工股份有限公司 Method for producing epoxypropane by using hydrogen peroxide and propylene
CN104230854A (en) * 2013-06-17 2014-12-24 中国石油化工股份有限公司 Cumyl hydroperoxide and propylene epoxidation method for preparing epoxypropane
CN104557780A (en) * 2013-10-28 2015-04-29 中国石油化工股份有限公司 Preparation method of epoxypropane
CN104557783A (en) * 2013-10-28 2015-04-29 中国石油化工股份有限公司 Method for producing epoxypropane from cumene hydroperoxide and propylene
CN104557779A (en) * 2013-10-28 2015-04-29 中国石油化工股份有限公司 Production method of epoxy propane
CN104557781A (en) * 2013-10-28 2015-04-29 中国石油化工股份有限公司 Method for producing propylene oxide
CN104557782A (en) * 2013-10-28 2015-04-29 中国石油化工股份有限公司 Method for preparing epoxypropane from cumyl hydroperoxide and propylene
CN105294606B (en) * 2014-07-24 2017-11-17 中国石油化工股份有限公司 The reaction method of hydrogen peroxide ethylbenzene and propylene expoxy propane
CN105272938A (en) * 2014-07-24 2016-01-27 中国石油化工股份有限公司 Epoxidation cyclic method for preparing epoxy propane from ethylbenzene hydroperoxide and propylene
CN105315235A (en) * 2014-07-24 2016-02-10 中国石油化工股份有限公司 Method used for realizing epoxidation of hydrogen peroxide ethylbenzene with propylene
CN105294605A (en) * 2014-07-24 2016-02-03 中国石油化工股份有限公司 Circulating method for preparation of propylene oxide from hydrogen peroxide ethylbenzene and propene
CN105272944A (en) * 2014-07-24 2016-01-27 中国石油化工股份有限公司 Method for preparing epoxy propane through epoxidation of ethylbenzene hydroperoxide and propylene
CN105461661B (en) * 2014-09-29 2018-07-31 中国石油化工股份有限公司 A kind of olefin oxidation method
CN106467505A (en) * 2015-08-20 2017-03-01 陕西煤业化工集团(上海)胜帮化工技术有限公司 HPPO legal system expoxy propane two-part reaction method
CN117986206A (en) * 2022-10-27 2024-05-07 中国石油化工股份有限公司 Epoxidation reaction method and system

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US6365761B1 (en) * 1999-08-18 2002-04-02 Shell Oil Company Process for preparing alkylene oxide

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US6646140B2 (en) 2003-11-11
DE60124682D1 (en) 2007-01-04
WO2001070712A1 (en) 2001-09-27
JP2001270879A (en) 2001-10-02
CN1196690C (en) 2005-04-13
BR0109333A (en) 2003-06-10
KR20030009397A (en) 2003-01-29
EP1266892B1 (en) 2006-11-22
KR100784119B1 (en) 2007-12-12
CA2403440A1 (en) 2002-09-19
CN1418200A (en) 2003-05-14
EP1266892A4 (en) 2004-09-29
AU2001241206A1 (en) 2001-10-03
ES2275660T3 (en) 2007-06-16
ATE346054T1 (en) 2006-12-15
US20030153775A1 (en) 2003-08-14
EP1266892A1 (en) 2002-12-18

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